Transformer



April 12, 1938. A. B. HENDRICKS, JR

TRANSFORMER Filed March 18, 1936 Patented Apr. 12, 1938 PATENT oI-FlcE TBANSFORMER Allan B. Hendricks, Jr.,

Pittsfield, Mass., assignor to General Electric Company, a corporation of New York Application March 18, 1936, Serial No. 69,488 l 2 Claims.

My invention relates to transformers and is particularly applicable in connection with a transformer having a low voltage winding of large cross section and rather few -turns and a high voltage winding of smaller cross section and a moderate number of turns, although there is 'no particular maximum limit to the number of turns in either winding. In a low voltage winding which must carry a heavy current, it is convenient to use a wide, flat conductor arranged .edgewise in a helix distributed along the winding leg of the transformer core, the turns oi the high voltage winding being arranged on both sides of each low voltage turn so that the two windings are well interleaved. This arrangement requires cross connections between high voltage winding turns surrounding opposite ends of the transformer winding leg.

The general object of the present invention is to provide an improved and compact transformer construction of the character referred to andl with the cross connections between turns so arranged as to be well protected and to form with the connected turns a continuous, jointless conductor.

'Ihe invention will be better understood from the following description taken in connection with the accompanying drawing in which Fig. 1 is a perspective view of a transformer constructed in accordance with the invention, parts being broken away to reveal details of the winding arrangement, and Fig. 2 is a diagrammatic view of the transformer with the parts widely separated to make the arrangement more clear.

Like reference characters indicate similar parts in both figures oi the drawing.

The transformer shown in Fig. l includes a magnetic core formed in two parts I0 and II placed side by side so that their adjacent sides form the winding leg of the core which is sur- .rounded by a low voltage winding I2 and a high voltage winding I3. The low voltage winding I2 is formed of a wide, flat conductor arranged edgewise in a helix with its turns spaced apart along the winding leg of the core I0, the two end turns being extended to form the low voltage terminals Il and I5. The high voltage winding I3 is preferably formed of stranded cable which is more or less flexible and thus may be conveniently curved and bent into place in the winding.

The high voltage winding I3 includes two groups of turns I6 and I1 at opposite sides of each turn of the low voltage winding I2 and a plurality of cross connections I8 for connecting (c1. 11s-35s) certain turns in series, as will appear later. 'I'he entire high voltage winding I3 is formed of a single, continuous conductor extending between its two terminals I9 and 20. This conductor formingthe high voltage winding -I 3 may be followed from the terminal I9 through the inner turn of the rst group of turns I6, a cross connection 2I, the inner turn of the second group of turns I6 and a cross connection 22 back to the second turn of the first group of turns I6. Thus the conductor continues through successive turns and cross connections through the last turn of the second group of turns` I8, whence it continues through the last cross connection 23, the inner turn of the `first group of turns I1, a cross connection 24, the inner turn of the second group of turns I1 and one of the cross connections I8 back to the second turn of the first group of turns I1. Thus the high voltage winding conductor continues successively through the turns of the groups of turns I1 to the last turn of the last group of turns I1 and thence to the high voltage winding terminal 20. The transformer is shown in Fig. 1 with ilve turns in each of the groups of turns I6 and I1 of the high voltage winding, but to avoid complication the groups of turns I8 and Il in Fig. 2 are shown as including only two turns each. Any reasonable number of turns may of course be used in these groups. The groups of turns I6 may be considered as a single group of turns extending along one face of the low voltage winding I2 and the groups of turns I1 may be considered as a single group extending along the other or opposite face of the low voltage winding I2, the turns of each group being connected in series by the connections 2|, 22, 24 and I8, and the two groups being connected in series by the single connection 23.

The cross connections I8 and 22 between winding turns near one end of the winding leg of the core and winding turns near the other end of the winding leg of the core pass through intermediate turns of both the windings, being disposed in the space between the core and these intermediate windings. Thus these cross connections are concealed and protected inside the transformer structure and the arrangement is compact and attractive in appearance. Another advantage of the arrangement which has been de- 'scribed is that the high voltage winding may be formed of a continuous, jointless conductor. It is customary to form the magnetic core of a transformer from sectional laminations which may be assembled after the winding has been completely formed. This procedure is desirable in producing the transformer oi' the present invention so that the cross connections Il and 22 may be easily placed in position before most o! the space within those turns already formed has been obstructed by the winding leg of the core. The drawing shows the cross connections Il and 22 passing through an insulating covering 25 which may of course be applied after the cross connections are in place.

The invention has been explained by describing and illustrating a particular transformer constructed in accordance therewith but it will be apparent that changes may be made without departing from the spirit of the invention and the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A transformer including a magnetic core having a winding leg, an edge-wise wound low voltage winding arranged in a helix with its turns spaced along said winding leg, a high voltage winding including a group of coils extending along each face of said low voltage winding. connections between the end turns oi successive coils to connect the coils of each group in series. said connections passing through the intermediate turns of said groups, and a. connection con- ALLAN B. HENDRICKS. Jl. 

